b 1. Field of the Invention
The present invention relates to machines for cleaning fibrous floor coverings, such as carpets and the like. More particularly, the present invention relates to a carpet cleaning machine for use in cleaning relatively large carpeted areas (e.g. carpeted hotel lobbies and hallways, theatre lobbies, convention rooms, etc.).
2. Description of the Prior Art
Recent years have seen a tremedous growth in the use of carpets as floor coverings. The use of carpets as a general purpose floor covering has been widespread in both commercial and residential building units. For example, most hotels, convention centers, shopping centers, theatres, and the like have relatively large carpeted areas. Such large carpeted areas present certain unique problems in terms of cleaning and maintaining the carpeting.
Many devices have previously been used for cleaning carpeting. One type of prior art carpet cleaning machine is generally known as a Shampoo-N-Vac unit and is manufactured by the Multi-Clean.RTM. Products Division of H. B. Fuller Company. This unit comprises a hand held wand which is placed in contact with the carpet to be cleaned. The wand has a fan jet nozzle for spraying a cleaning solution under pressure into contact with the carpet. The wand also contains a vacuum head for picking up the cleaning solution and the dislodged dirt from the carpet. The Shampoo-N-Vac unit does not utilize any positive agitation of the carpet fibers other than that provided by the cleaning solution spray. Two additional hand held units for cleaning carpeting are known generally by the trade names of Karpet Champ.RTM. and Carpet Pro. These units are also manufactured by the Multi-Clean.RTM. Products Division of H. B. Fuller Company and operate on generally similar principles. Both the Karpet Champ.RTM. and the Carpet Pro units have a rotatable brush for agitating the carpet fibers as a foamed cleaning medium is applied thereto. A liquid cleaning solution is held in a container on the handle of the cleaning unit and is foamed as it is being dispensed towards the carpeting. However, after the foamed cleaning medium has been applied to the carpet and agitated by the brush, it is left to dry on the carpet. This requires that the cleaning medium be vacuumed up thereafter.
Although the above-noted carpet cleaning units are quite effective in cleaning carpeting and other fibrous floor coverings, they are not designed for efficiently cleaning large carpeted areas. For one thing, because these units are hand held, the rate of cleaning depends partially on the rate at which an operator can manually move the units in contact with the carpet. In addition, with regard to the cleaning units known as the Karpet Champ.RTM. and the Carpet Pro, the need to go back and vacuum off the dried cleaning medium increases the time necessary for cleaning the carpet. Although such a time increase is not significant when cleaning relatively small areas of carpeting, the same increase is quite significant when cleaning large expanses of carpeting.
Other devices have also been previously used for cleaning capeting. Some of these devices generally comprise a hand operated cleaning unit having an undriven roller or support wheel, a series of spray nozzles for spraying a liquid cleaning solution into contact with the carpet, a brush means for agitating the carpet, and a vacuum shoe for picking up the cleaning solution from the carpet. This type of device is operated by dragging the cleaning unit across the carpeting in a rearward direction rather than by pushing the unit in a forward direction. This is to ensure that the cleaning unit does not roll over the area of carpeting which has just been cleaned. In addition, a second auxilary unit is provided for storing a supply of the cleaning fluid therein. The auxilary unit also provides a vacuum source which may be connected to the vacuum shoe for drawing up the spent cleaning solution from the carpeting.
Although this latter type of unit is somewhat more effective in cleaning large carpeted areas than the units first described above, this unit still has various disadvantages in performing such a task. These disadvantages result partially from the fact that two separate units are needed (i.e. both a hand operated cleaning unit and a separate auxilary storage unit). Both of these units must be separately moved and set up in a cleaning position. In addition, various elongated flexible hoses must be provided for connecting the two units together. Moreover, an operator can only clean the area immediately adjacent to the storage tank over the area of reach of the connecting hoses. When the operator desires to clean an area outside this reach, the storage unit must first be repositioned. The operator must also manually push or move the cleaning unit to clean the carpeting. All of the above factors increase both the amount of time needed to clean the carpeting and the difficulty which the operator encounters in using the machine.
Another prior art cleaning device is generally similar to the machines just described in that a separate storage unit and a separate cleaning unit are provided. In addition, the cleaning unit of this device utilizes a plurality of rotating jets for spraying the cleaning solution into contact with the carpeting. These jets are motor driven so that the solution also agitates the carpet fibers. However, the necessary drive mechanism for these jets increase the purchase cost and complexity of this machine. In addition, this machine has the various disadvantages of the dual unit cleaning machines noted above.
Other cleaning machines are known which utilize a cleaning solution storage tank that is incorporated with a plurality of cleaning brushes on a power driven movable body. Examples of such a machine are the 21B and 21E Automatic Scrubbers, manufactured by the Multi-Clean.RTM. Products Division of H. B. Fuller Company. In this machine, a cleaning solution is first applied to a floor surface. A plurality of brushes which rotate about a vertical axis are arranged at the front of the machine to scrub the floor surface after application of the cleaning solution. A vacuum squeegee is mounted at the rear of the machine to pick up the cleaning solution from the floor surface. However, the 21B and 21E Automatic Scrubbers are not suitable for cleaning fibrous floor covering such as carpeting. These machines have been designed for cleaning only relatively hard floor surfaces, such as stone or brick floors and the like.